View full sizeThe Associated PressThe depot destroyed the last of its chemical weapons in October.

Oregon environmental regulators announced a $46,800 penalty against the operators of the Umatilla Chemical Depot on Tuesday, bringing total depot penalties to nearly $800,000 since 1999.

Washington Demilitarization Co., a division of the URS Corp., is in charge of incineration at the U.S. Army's depot, which finished destroying 3,720 tons of mustard "blister" agent and sarin and VX nerve agents in October.

The four violations announced Tuesday came in June and September, the Department of Environmental Quality said. They involved excess carbon monoxide emissions during mustard agent incineration, air monitoring failures and improper maintenance of monitoring equipment.

As with the violations in 24 prior penalties since 1999, none of the latest violations harmed the environment or public health, DEQ said. Washington Demilitarization reported the violations.

Three of the violations announced Tuesday were similar to violations within the past two years, increasing the amount of the proposed penalty, DEQ said.

"Based on the past problems, they should have paid extra attention," said Sarah Wheeler, an environmental law specialist with DEQ.

The latest violations and the long list of penalties since 1999 also reflect the complexity of the operation, which included up to four hazardous waste incinerators, DEQ officials said. The state's permit for the depot takes up two 3-inch-thick binders.

"Most of (the violations) could have been prevented, but it's not because they're running a sloppy operation out there," Wheeler said. "With something so complex and so strictly regulated, there are going to be mistakes."

Hal McCune, protocol officer for Washington Demilitarization, said backup controls and monitoring systems would have caught emissions of serious concern. None of the emissions reached workers, he said.

Washington Demilitarization began chemical weapons destruction in 2004. It has paid $292,000 in penalties since 1999, according to DEQ records, and agreed to fund $332,000 in environmental projects, including programs to cut wood stove pollution in Pendleton and Grant County.

The company is appealing another $155,000 in proposed penalties since November 2010, including the latest one. The penalties could be reduced on appeal.

The penalties are large for Oregon, reflecting the risks of the operation, but are a sliver of the project's $2.7 billion estimated cost. During weapons destruction, operating costs totaled $300,000 to $400,000 a day, McCune said.

Two incinerators still burn lower-level hazardous waste left from weapons destruction, primarily a metals furnace to process pipes and worker suits and tools, McCune said. That work should be finished by the end of 2014.

"We don't want to say we're not going to get penalized again," he said, "but with the munitions gone and the munitions processing done, it's far less likely."

Umatilla and six other facilities have destroyed their inventory, eliminating nearly 90 percent of the Army's chemical agent stockpile. Depots in Kentucky and Colorado are scheduled to destroy the remainder.